Are there any gotta have it apps in the Windows 8 store, metro or other?

After initially installing Win8, i tried out all the built-in metro apps and looked in the store for anything that caught my eye.  That experience proved that all the metro apps were pretty horrible and barely functional, so I've never gone back.

Am I missing anything?  Any really good apps everyone should know about?

I use the graffiti app to stream pandora.  Its worth it.